FIGS. 1 through 3 show a conventional linear compressor, which includes a predetermined shaped cylinder 2 disposed within a housing 1 of the linear compressor, and a stator 3 disposed at the outside of the cylinder 2 for generating a magnetic field therearound.
A horizontal operating unit 4, which horizontally reciprocates in cooperation with the stator 3, is disposed at one side of the cylinder 2.
The horizontal operating unit 4 includes' a magnet 5 which horizontally reciprocates within the stator 3 in cooperation with an alternating magnetic force generated by the stator 3; a piston 6, which is integral with the magnet 5 and reciprocates within the cylinder 2; a piston spring 7 disposed at the piston 6 and the magnet 5 for generating a predetermined elastic force, and a mounting spring 8 disposed at a predetermined portion of the housing 1 for supplying an elastic energy to the piston spring 7.
A predetermined amount of a coolant 9 is filled at the lower portion of the housing 1.
At the other side of the cylinder 2, there is provided a valve plate 10 including a suction gasket 11, a suction valve sheet 12, a valve sheet 13, a discharging valve sheet 14, and discharging gasket 15 in order for the refrigerant gas to be sucked into or discharged from the cylinder 2.
A suction portion muffler 16 and a discharging portion muffler 17 are provided at a predetermined portion of the valve plate 10. A head cover 18 is disposed at the upper portion of the suction portion muffler 16 and the discharging portion muffler 17 in order for the above-mentioned elements to be fixed to the cylinder 2.
The suction gasket 11 is disposed between the suction valve sheet 12 and the cylinder 2 for preventing the leakage of the coolant gas. A first sucking/discharging hole 19 is formed at the center portion of the suction gasket 11 for sucking/discharging the refrigerant gas therethrough.
A suction opening portion 20 is formed at the central portion of the suction valve sheet 12 for being opened by the suction force or the discharging force of the coolant gas, and a first discharging hole 21 is formed at one side of the suction opening portion 20.
A first suction hole 22 is formed at the central portion of the discharging valve sheet 14 in order for the refrigerant gas to be sucked therethrough, and a discharging opening/closing portion 23 is formed at one side of the suction hole for being opened/closed by the suction force or the discharging force of the coolant gas.
The valve sheet 13 is positioned between the suction valve sheet 12 and the discharging valve sheet 14. A second suction hole 24 is formed at the central portion of the valve sheet 13 in order for the refrigerant gas to be sucked therethrough, and a second discharging hole 25 is formed at one side of the second suction hole 24 in order for the refrigerant gas to be discharged.
A discharging gasket 15 is positioned between the discharging valve sheet 14 and the head cover 18 for preventing the leakage of the coolant gas, and a second sucking/discharging hole 26 is formed at the central portion of the discharging gasket 15 in order for the refrigerant gas to be sucked/discharged therethrough.
A capalliar tube 27 is disposed at a predetermined portion of the suction muffler 16 in order for the coolant oil 9 to be sucked into the suction muffler 16 in cooperation with the suction force of the piston 6.
The operation of the conventional linear compressor will now be explained with reference to the accompanying drawings.
First, when the stator 3 is supplied with a current, a magnetic field is formed therearound. The thusly formed magnetic field alternately communicates with the magnetic field generated by the magnet 5, so that a horizontal movement of the piston 6 of the horizontal operating unit 4 is made.
Thereafter, the refrigerant gas sucked into the suction muffler 16 in cooperation with the suction force of the piston 6 passes through the second suction/discharging hole 26 of the discharging gasket 15, the first suction hole 22 of the discharging valve sheet 14, and the second suction hole 24 in order, and then pushes the suction opening/closing portion 20 of the valve sheet 13, and is introduced into the cylinder 2 through the first sucking/discharging hole 19 of the suction gasket 11. At this time, the suction force of the piston 6 pushes the discharging opening/closing portion 23 of the discharging valve sheet 14 so as to close the second discharging hole 25 of the valve sheet 13.
Meanwhile, the coolant oil 9 introduced into the suction muffler 16 together with the refrigerant gas in cooperation with the suction force of the piston 6 serves as a lubricant in the cylinder 2 after it is introduced into the cylinder 2 through the valve plate 10.
Thereafter, when the refrigerant gas and the coolant oil 9 are compressed by the reciprocating movement of the piston 6, the refrigerant gas in the cylinder 2 passes through the first sucking/discharging hole 19 of the suction gasket 11, the first discharging hole 21 of the suction valve sheet 12, and the second discharging hole 25 of the valve sheet 13. The gas then pushes through the discharging opening/closing portion 23 of the discharging valve sheet 14 and passes to the discharging muffler 17 through the second sucking/discharging hole 26 of the discharging gasket 15.
Meanwhile, the coolant oil is discharged together with the refrigerant gas in cooperation with the discharging force of the piston 6 along the same path as the coolant gas.
The coolant oil 9 introduced into the cylinder 2 is discharged such that the coolant oil 9 is not substantially provided between the cylinder 2 and the piston 6. The lubricant operation in the system is therefore degraded, and the heat generated within the cylinder 2 can not be substantially cooled.
In addition, since a lot of coolant oil 9 is discharged, the discharging force of the refrigerant gas compressed in the cylinder 2 is weakened.
Moreover, the refrigerant gas sucked into and discharged from the valve plate 10 may leak.